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September 9, 1998. This is an article that was published in Wild Earth (A
journal for creatures who care about their habitat. P.O. Box 455, Richmond,
Vermont, 05477) Vol. 7, No. 3, Fall 1997, Pgs. 88-90. It has been slightly
My answer to the question is "YES" there is a problem. The scale of human activities is now so large that we are appreciably affecting the climate and ecosystems in the U.S. and the world.
The total impact of people on the environment is proportional to each of two factors:
A) The number of people, and
B) The average impact of each person.
If we are to reduce the total impact of people on the global environment, we must address the first, or preferably both, of these factors.
There are many strong forces that will cause continued growth of the average impact of each person on the global environment. To the extent that people in underdeveloped countries seek to increase their material standard of living to levels more like ours, material consumption per capita will grow. So we are left with the imperative of halting population growth, and then of studying the question, "Can this stable population be sustained?"
To gain a better appreciation of the seriousness of the problem, let us review some very elementary arithmetic. Let us consider a quantity that is experiencing steady growth at a rate such as 5% per year.
First we note that this growing quantity will double in size in a fixed time. This doubling time is found by dividing 70 by the percent growth per year. For example, the doubling time for a steady growth rate of 5% per year is 70 / 5 = 14 years.
Second, we note that a few doublings can give enormous numbers. It is convenient to remember that ten doublings causes the growing quantity to increase in size by a factor of approximately 1000: twenty doublings will cause an increase by a factor of 1,000,000, etc.
Let us look at some current approximate, data (1997).
The smallness of the annual growth rates is both deceiving and disarming. We might initially think that surely nothing bad could happen at growth rates as small as 1% or 1.6% per year. A study of the doubling times brings us back to reality. If the world population continues to grow at its present rate, it will double before today's (1997) college students are my age (74)! Think what this means in terms of food and resource consumption.
Population growth rates do not remain constant; they change in response to physical and social factors. The world population growth rate was close to zero through most of human history, and it started to increase significantly a few centuries ago. Around 1970 it reached a high of about 2% per year, from which it has recently declined to the estimated 1.6% per year. Detailed social studies and more elegant mathematical models can give us insight into the mechanisms that affect these rates of growth.
Why, then, do we need to look at the simple models of constant growth rates?
First, they are a useful, though approximate, representation of the facts.
Second, we in the United States are in a culture that worships growth. Steady growth of populations of our towns and cities is the goal toward which the powerful promotional groups in our communities continuously aspire. If a town's population is growing, the town is said to be "healthy," or "vibrant," and if the population is not growing the town is said to be "stagnant." Something that is not growing should properly be called "stable." Yet, the promoters of growth universally use the word "stagnant" to describe the condition of stability, because "stagnant" suggests something unpleasant while "stable" would suggest something worthwhile, pleasant and desirable.
Since continued growth is the goal of the promoters in our communities, we should understand the arithmetic of steady growth.
Now let's look at some global aspects of our population problem.
All of these problems are caused by population growth, and none of these problems can be "solved" if population growth continues.
Today we hear many people talking about "Sustainability," as though we can accomodate continued population growth with something vague and ill-defined that is called "sustainable development." The thought seems to be that there is no need to worry about population: all we need to do is to make minor modifications of our way of life, (conserve, recycle, etc.) and this will suffice to make our society "sustainable." Please remember the First Law of Sustainability:
It is not possible to sustain population growth or growth in the rates of consumption of resources.
We now must address two questions:
For many people, the population problem is a problem of "those people," in distant undeveloped countries. In early 1997, many people succesfully lobbied Congress to restore family planning assistance in the U.S. foreign aid programs. This was a great victory, but it treats "those people" as though they were the big problem. As one member of Congress said,
Unchecked population growth in the Third World means depletion of water resources. It means famine. It means suffering. It pushes populations to clear rainforests. It pushes populations to go out and graze on land that cannot sustain cattle, and that leads to expansion of deserts worldwide. We all have a stake in the global environment.
It is so easy to blame the problem on others and to identify what other people should do to solve the problem, while we ignore our own responsibilities and avoid doing anything to reduce the population problem in the U.S. We need to work to stop population growth in the U.S.
There are two sources that contribute approximately equally to population growth in the U.S.: the excess of births over deaths, and immigration. Both of these must be addressed.
Let's compare three aspects of efforts to stop population growth in other countries with efforts to stop population growth in the United States.
As you think about addressing the problem of population growth in the U.S., please ponder this challenge:
Can you think of any problem, on any scale, from microscopic to global, Whose long-term solution is in any demonstrable way, Aided, assisted, or advanced, by having continued population growth At the local level, the state level, the national level, or globally?
So we can see that Pogo was right:
"We've met the enemy, and they's us!"
Albert A. Bartlett is an Emeritus Professor of Physics University of Colorado at Boulder (80309-0390)
(See the Al Bartlett website, which contains a collection of Al Bartlett's works, presentation, and video.)
Professor Bartlett lectures regularly to a wide variety of audiences from coast to coast on the topic "Arithmetic, Population, and Energy." In 29 years he has given this lecture over 1280 times.
A one-hour videotape of this lecture is available from the Department of Information Technology Services University of Colorado at Boulder (80309-0379); Contact Kathleen Albers, (303) 492-1857
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